10 Amazing Phenomena of a Normal Human Mind

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The clustering illusion is the illusion that random events which occur in clusters are not really random events. The illusion is due to a counter-intuitive assumption about statistical odds.

For example, it strikes most people as unexpected if heads comes up four times in a row during a series of coin flips. Now if you have got 3 consecutive heads, you’d think next flip can’t be heads, though there is still a 50% probability. Thinking that the probabilities have changed is a common bias. This has caused gamers to lose thinking the probability has changed.

9. Reverse Psychology

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Do you sometimes do things just because somebody said you shouldn’t? Aren’t you sometimes tempted to do them? When you do something that is forbidden, you may be demonstrating reactance as your motivation. Reactance is a drive to do something you’ve been told (threatened) not to do. We may respond with reactance because we humans just don’t like it when somebody takes away our freedom to choose how we behave. In fact, reactance theory is sometimes called “ forbidden fruit” theory.

The theory assumes there are “free behaviors” individuals perceive and can take part in at any given moment. The level of reactance has a direct relationship to the importance of eliminated or threatened behavioral freedom in relationship to the importance of other freedoms at the time.

8. Paramnesia

Paramnesia also called as Déjà Vu, is when an individual feels as though an event has already happened or has happened in the recent past. The experience of paramnesia seems to be quite common among adults and children alike. Paramnesia or déjà vu is usually accompanied by a compelling sense of familiarity, and also a sense of “eeriness,” “strangeness,” “weirdness”. Certain researchers claim to have found ways to recreate this sensation using hypnosis.

The similarity between a déjà-vu-eliciting stimulus and an existing, but different, memory trace may lead to the sensation. Thus, encountering something which evokes the experience or sensation that cannot be remembered may lead to déjà vu.

7. Apophenia

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Apophenia is the experience of seeing patterns or connections in random or meaningless data. Pareidolia is a type of apophenia involving a vague and random stimulus (often an image or sound) being perceived as significant. Common examples include seeing images of animals or faces in clouds, the man in the moon, and hearing hidden messages on records played in reverse.

There have been many instances of perceptions of religious imagery and themes, especially the faces of religious figures. In 1978, a New Mexican woman found that the burn marks on a tortilla appeared similar Jesus’s face. Thousands of people came to see the framed tortilla.

6. Horn’s Effect

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Horn’s Effect, also called the devil’s and reverse halo effect is where individuals, brands or other things judged to have a single undesirable trait are subsequently judged to have many poor traits. Allowing a single weak point or negative trait to influence perception of the person, brand or other thing in general. Simplifying it, when we consider a person bad in one area, we are likely to make a similar evaluation in other areas.

There is not a 50% chance of getting 20 heads in a row. If you want to get 20 in a row the chance of getting that is .5^20. The chance every time of getting heads is .5, but to get 20 in a row the probability is much smaller than that.

You seem to have misread it. It clearly states that in a series of 20 flips, the chance of a string of four heads in a row some time during the series is 50%.
Which is correct, out of all the possibilities for 20 flips, half contain four heads in a row.